The invention relates to a flanged pipe part made of fibre-reinforced thermosetting synthetic resin comprising at least a tubular part, extending in an axial direction, which is fitted, or can be fitted, on a tubular body to be provided with a tubing body, which tubular part adjoins the inside face of the flange which, together with the outside face of the flange, defines the flange. The flanged pipe part has several fibre-reinforcement layers laid around each other and extends in an axial direction, which are spirally wound thereabout and the tubular part also consists of fibre-reinforced layers of thermosetting synthetic resin.
Such a flange pipe part comprises fibre-reinforcement layers extending exclusively in the axial direction, which layers are spirally wound, the distance from the axis of the flange of at least one layer from the axis of the flange varying in a plane extending axially through the axis of the flange over the width of the fibre-reinforcement layer, which variation is formed during the winding, and is known from the Dutch Patent Application No. 7,810,838. When such fibre-reinforcement layers are used in a flange pipe part, said reinforcement layers lie irregularly on top of each other, as a result of which the shearing forces in the axial direction which are necessary to cause the layers to slide off are much greater than should a smooth roving be used or if fibre-reinforcement layers were used which extended precisely concentrically.
An advantage of said flange is that it is quicker to manufacture than the previously known flange, is stronger in the axial direction and, in addition, can be manufactured in a more reproducible manner.
The known flange does, however, have the disadvantage that, in the angular intersection between the inside face of the flange and the flange section extending in the axial direction and adjacent thereto, microcracks readily occur which, of course, have a very disadvantageous effect on the strength of the flange. Although said microcracks cannot generally be perceived with the naked eye, they can readily be revealed by the action of a dye stuff.